Steam generating device

ABSTRACT

A steam generating device includes a body having a waterway defined longitudinally therein, and an inlet and an outlet are respectively connected to the body and communicate with the waterway. A heating tube is connected to the body and located close to the waterway. A pre-heat tube is connected to outside of the body and has a first end for introducing cold water into the pre-heat tube and a second end connected to the inlet. The cold water is pre-heated in the pre-heat tube before entering the waterway so that the water in the waterway is easily transferred into steam.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a steam generating device, and more particularly, to a steam generating device having a pre-heat tube to increase the efficiency for generating steam.

2. Description of the Prior Art

A conventional steam generating device is cooperated with a water tank from which water is pumped into the steam generating device and heated to generate steam. The steam is ejected from an outlet to clean stains or kill germs or even to iron wrinkles of fabrics.

The conventional steam generating device is shown in FIG. 5 and generally includes a body 60 which includes a waterway 61 defined longitudinally therein. An inlet 61 and an outlet 63 are respectively connected to the body 60 and communicate with the waterway 61. A U-shaped heating tube 70 is connected to the body 60 and located close to the waterway 61. Two free ends 71 of the heating tube 70 are exposed from the body 60 and connected to a power source which is not shown. The heating tube 70 generates high temperature which is absorbed by the way in the waterway 61 so as to transfer the water in the waterway 61 into steam which is ejected from the outlet 63.

However, the length of the body 60 is limited so as to be installed into the casing of the appliance so that the time that the water in the waterway is too short to be heated to become steam. What ejected from the outlet 63 is a mixture of water and steam, and the mixture containing too much water and has lower temperature than expected.

The present invention intends to provide a steam generating device which includes a pre-heat tube such that water is pre-heated before entering into the waterway and the steam ejected from the outlet contains less water and has high temperature.

SUMMARY OF THE INVENTION

The present invention relates to a steam generating device that comprises a body having a waterway defined longitudinally therein. An inlet and an outlet are respectively connected to two ends of the body and communicate with the waterway. A heating tube is connected to the body and located close to the waterway. A pre-heat tube is connected to the body and located close to the heating tube. The pre-heat tube includes a first end and a second end, wherein the first end introduces cold water into the pre-heat tube and the second end is connected to the inlet so as to deliver the pre-heated water into the waterway.

The primary object of the present invention is to provide a steam generating device that generates steam containing less water and has high temperature by suing a pre-heat tube.

The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view to show the steam generating device of the present invention;

FIG. 2 is an exploded view to show the body, the pre-heat tube and the connection tube of the present invention;

FIG. 3 shows the steam generating device is installed in an appliance;

FIG. 4 is a perspective view to show the steam generating device of the present invention having a spiral pre-heat tube, and

FIG. 5 is a cross sectional view to show the conventional steam generating device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 and 2, the steam generating device of the present invention comprises a metallic and elongate body 60, a U-shaped heating tube 70, a U-shaped pre-heat tube 10 and a connection tube 20. The body 60 and the heating tube 70 are similar to those disclosed in the conventional steam generating device. The body 60 has a waterway 61 defined longitudinally therein. An inlet 61 and an outlet 63 are respectively connected to two ends of the body 60 and communicate with the waterway 61. The U-shaped heating tube 70 is connected to the body 60 and located close to the waterway 61. Two free ends 71 of the heating tube 70 are exposed from the body 60 and connected to a power source which is not shown.

The body 60 has a recess 32 defined in an outside 30 thereof and the recess 32 is located close to the heating tube 70. The pre-heat tube 10 is received in the recess 32. The pre-heat tube 10 includes a U-shaped tubular body 11 which has the first end 12 and the second end 13. The first end 12 introduces cold water into the pre-heat tube 10 and the second end 13 is connected to the inlet 62 to the body 60. The connection tube 20 includes a first connection end 21 and a second connection end 23, the first connection end 21 is connected to the inlet 62 of the body 60 and the second connection end 23 is connected to the second end 13 of the pre-heat tube 10.

The cold water is introduced into the pre-heat tube 10 via the first end 12 of the pre-heat tube 10 and the water in the pre-heat tube 10 is pre-heated by the heating tube 70. The pre-heated water then flows into the waterway 61 via the connection tube 20 and the inlet 62. Because the water entering the waterway 61 is pre-heated, so that the temperature of the pre-heated water can be easily raised and transferred into steam. In other words, the travel distance of the water is increased while the size of the body 60 does not change too much, and the efficiency is increased.

FIG. 3 shows an appliance 40 includes a space 41 defined therein and the body 60 and the pre-heat tube 10 are located in the space 41 and enclosed by a casing 42. The connection tube 20, the free ends 71 of the heating tube 70 and the outlet 63 are exposed from the casing 42. The outlet 63 is in communicating with the nozzle 43 from which the steam is ejected.

FIG. 4 shows another embodiment of the pre-heat tube 101 which has a spiral tubular body 111 and spirally located around the body 60. The second end 13 of the pre-heat tube 101 is connected to the inlet 62 and the first end of the pre-heat tube 101 introduces cold water into the pre-heat tube 101.

The pre-heat tube 10 is received in the recess 32 in the outside 30 of the body 60 so that the size of the body 60 does not need to change too much and can still be installed in the appliances. The travel distance of the water is increased and the time for absorbing the heat is increased so that the water can be transferred into steam efficiently. The casing 42 encloses the pre-heat tube 10 and the body 60 to reduce heat loss during operation.

While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention. 

1. A steam generating device comprising: a body having a waterway defined longitudinally therein, an inlet and an outlet respectively connected to the body and communicating with the waterway, a heating tube connected to the body and located close to the waterway, and a pre-heat tube connected to the body and having a first end and a second end, the first end adapted to introduce cold water into the pre-heat tube and the second end connected to the inlet.
 2. The device as claimed in claim 1, wherein the pre-heat tube has a U-shaped tubular body which includes the first end and the second end, a connection tube includes a first connection end and a second connection end, the body has a recess defined in an outside thereof and the recess is located close to the heating tube, the pre-heat tube is received in the recess and the first connection end is connected to the inlet of the body and the second connection end is connected to the second end of the pre-heat tube.
 3. The device as claimed in claim 1, wherein the pre-heat tube has a spiral tubular body which spirally located around the body, the second end of the pre-heat tube is connected to the inlet and the first end of the pre-heat tube adapted to introduce cold water into the pre-heat tube. 